GDSII stream format (GDSII), is a binary

database In computing, a database is an organized collection of data stored and accessed electronically. Small databases can be stored on a file system, while large databases are hosted on computer clusters or cloud storage. The design of databases sp ...

file format A file format is a standard way that information is encoded for storage in a computer file. It specifies how bits are used to encode information in a digital storage medium. File formats may be either proprietary or free. Some file formats ...

which is the de facto industry standard for

Electronic Design Automation Electronic design automation (EDA), also referred to as electronic computer-aided design (ECAD), is a category of software tools for designing Electronics, electronic systems such as integrated circuits and printed circuit boards. The tools wo ...

data exchange of

integrated circuit An integrated circuit or monolithic integrated circuit (also referred to as an IC, a chip, or a microchip) is a set of electronic circuits on one small flat piece (or "chip") of semiconductor material, usually silicon. Large numbers of tiny ...

IC layout Integrated circuit layout, also known IC layout, IC mask layout, or mask design, is the representation of an integrated circuit in terms of planar geometric shapes which correspond to the patterns of metal, oxide, or semiconductor layers that make ...

artwork. It is a

binary file A binary file is a computer file that is not a text file. The term "binary file" is often used as a term meaning "non-text file". Many binary file formats contain parts that can be interpreted as text; for example, some computer document fil ...

format representing planar geometric shapes, text labels, and other information about the layout in hierarchical form. The data can be used to reconstruct all or part of the artwork to be used in sharing layouts, transferring artwork between different tools, or creating

photomask A photomask is an opaque plate with holes or transparencies that allow light to shine through in a defined pattern. They are commonly used in photolithography and the production of integrated circuits (ICs or "chips") in particular. Masks are used ...

History

GDS = Graphic Design System (see DS78 Initially, GDSII was designed as a stream format used to control integrated circuit photomask plotting. Despite its limited set of features and low data density, it became the industry conventional stream format for transfer of IC layout data between design tools of different vendors, all of which operated with proprietary data formats. It was originally developed by

Calma Calma Company, based in Sunnyvale, California, was, between 1965 and 1988, a vendor of digitizers and minicomputer-based graphics systems targeted at the cartographic and electronic, mechanical and architectural design markets. In the electroni ...

for its layout design system, "Graphic Design System" ("GDS") and "GDSII". GDSII files are usually the final output product of the IC design cycle and are handed over to IC foundries for IC fabrication. GDSII files were originally written on

magnetic tape Magnetic tape is a medium for magnetic storage made of a thin, magnetizable coating on a long, narrow strip of plastic film. It was developed in Germany in 1928, based on the earlier magnetic wire recording from Denmark. Devices that use magne ...

. Objects contained in a GDSII file are grouped by assigning numeric attributes to them including a "layer number", "datatype" or "texttype". While these attributes were designed to correspond to the "layers of material" used in manufacturing an integrated circuit, their meaning rapidly became more abstract to reflect the way that the

physical layout Integrated circuit layout, also known IC layout, IC mask layout, or mask design, is the representation of an integrated circuit in terms of planar geometric shapes which correspond to the patterns of metal, oxide, or semiconductor layers that make ...

is designed. As of April 2008, many

EDA EDA or Eda may refer to: Computing * Electronic design automation * Enterprise Desktop Alliance, a computer technology consortium * Enterprise digital assistant * Estimation of distribution algorithm * Event-driven architecture * Exploratory ...

software vendors have moved to the stream format

OASIS In ecology, an oasis (; ) is a fertile area of a desert or semi-desert environment'ksar''with its surrounding feeding source, the palm grove, within a relational and circulatory nomadic system.” The location of oases has been of critical imp ...

, which replaced GDSII.Going from GDSII to OASIS
Philippe Morey-Chaisemartin (Xyalis) // EETimes 8/4/2008

GDSII utilities

As the GDSII stream format is a de facto standard, it is supported by nearly all EDA software. Besides the commercial vendors there are plenty of free GDSII utilities. These free tools include editors, viewers, utilities to convert the 2D layout data into common 3D formats, utilities to convert the binary format to a human readable ASCII format and program libraries.Octave and MATLAB toolbox for reading and writing GDSII layout files https://sites.google.com/site/ulfgri/numerical/gdsii-toolbox

Notes

References

* Clein, Dan. (2000). ''CMOS IC Layout''. Newnes. {{ISBN, 0-7506-7194-7
* DS78Calma. (1978). ''GDS II Graphic Design System User's Operating Manual'', First Edition 1978. Online at http://www.bitsavers.org/pdf/calma/GDS_II_Users_Operating_Manual_Nov78.pdf Retrieved Apr 21, 2020.

External links

Computer Aids for VLSI Design - Appendix C: GDS II Format
by Steven M. Rubin // Addison-Wesley, 1987

by Jim R. Buchanan, 6/11/96
GDS II Graphic Design System User's Operating Manual, First Edition 1978
// Calma Interactive Graphic Systems, November 1978. Retrieved Apr 21, 2020.
GDSII™ Stream Format Manual (B97E060), Release 6.0
// Calma, February 1987 * SPIE Handbook of Microlithography, Micromachining and Microfabrication, Vol. 1: Microlithography // Bellingham, Wash. : SPIE Optical Engineering Pr., 1997

EDA file formats

History

GDSII utilities

See also

Notes

References

External links